Interest calculator



July 28, 1925.

F. G.' PORTER INTEREST CALCULATOR Filed March 1923 4 Sheets-Sheet l gwventoz 776. i'Tok'rEl'f,

MWess/Es 7 5M 624 Ottoman July 28, 1925. 1,547,264

- F. G. PORTER INTEREST CALCULATOR Filed March 29, 192s Sheets-Sheet 2 v 1 q l All F. G. PORTER INTEREST CALCULATOR July 23, 11925. 1,547,261

Filed March 29, 1923 4 Sheets-Sheet 3 1 6 July28, 1925 F. G. PORTER INTEREST CALCULATOR Filed March 29, 19 23 4- Shaats-Sheet 4 Wan Patented July 28, 1925.

UNITED STATES FRANK G; PORTER, OF PATEROS, WASHINGTON.

INTEREST CALCULATOR.

Application filed March 29, 1923.

To all whom it may concern.

Be it known that I, FRANK Gr. PORTER, a citizen of the United States, residing at Pateros, in the county of Okanogan and State of Washington, have invented certain new and useful Improvements in an Interest Calculator, of which the following is a speciiication.

This invention relates to novel means for calculating interest and the primary object of the invention is to provide a device of compact structure for use in banking and other houses, which is so constructed, that the amount of interest due on notes and the like can be quickly found for any amount, and for any length of time.

Another object of the invention is to' provide novel means for quickly computing the length of time between any two dates, so that the amount of interest due on a certain amount for a pre-determined length of time can be quickly found.

A further object of the invention is to provide novel means associated with the time calculating. device for giving the amount of interest due on different amounts for difiierent lengths of time.

A still further object of the invention is to provide an improved interest calculator of the above character, which is durable and eflicient in use, one that is simple and easy to manufacture, and one which can be placed upon the market at a reasonable cost.

Vith these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as will be hereinafter more specifically described, claimed and illustrated in the accompanying drawings, forming a part of this specification, in which drawings:

Figure 1 is a top plan view of the improved interest calculator.

Figure 2 is an end elevation of the same.

Figure 3 is a transverse section through the improved calculator taken on the line 33 of Figure 1.

Figure 4' is a top plan view of the time calculating device;

Figure 5 is a transverse section through the calculating device taken on the line 55 of Figure 4.

Figure 6 is a fragmentary detail perspective view of the cylinder carrying the interest tables.

Figure 7 is a detail perspective view of Serial No. 628,623.

the marker associated with the improved interest calculating device.

Figure 8 is a fragmentary top plan view of a slightly modified construction.

Referring to the drawings in detail, wherein similar reference characters designate corresponding parts throughoutthe seveal views, the letter A generally indicates the improved interest calculator which includes the casing B, the time calculating portion C, the interest calculating portion D and the marker E.

The casing or housing B can be of any preferred form and constructed of any de sired material, and as shown the same includes side walls 10, end walls 11, and a top wall 12, which is provided with longitudinally extending sight openings or slots 13 and 14, through which is adapted to respectively appear the time calculating device G and the interest calculating device D. The slot 13 is arranged adjacent to the front edge of the casing B, while the slot 14 is arranged inwardly of the slot 13.

The time calculating device C comprises a stationary scale 15 and a movable scale or slide 16. As shown the stationary scale 15 consists of three spaced longitudinally extending sections 17 1 8 and 19 mounted upon a base plate 20. The spaces between the sections 17, 18 and 19 define grooves 21 slidably receiving the three sections 21, 22

and 23 forming a part of the movable slide.

As shown the terminals of these sections 21, 22 and 23 are connected by end pieces 24 and 25. These end pieces 24k and 25 are connected in any preferred manner to end rollers 26, or they may be omitted entirely, and the ends of the ribbons joined to form an endless belt. Each roller is provided with an outwardly extending manipulating handle 27 and it is obvious that by turning the handles that the slide can be moved or adjusted along the scale 15.

As clearly shown in Figure 4 of the drawings each section 17, 18 and 19 of the'memher is divided by a longitudinally extending line 28 into two columns and these columns are ruled into transverse spaces. These transverse spaces in the columns on the right of the lines 28 are numbered in chronological order from O to 365 and as shown the 1 starts at the lower end of the right-hand column of section 19 and terminateat the upper end of the right-hand column of the section 17. The columns to the left of the lines 28 are numbered in chronological order from 0 to 365 and it can be seen that the number starts with 0 at the upper end of the left-hand column of the section 17 and.

and the days of the months are arranged in chronological order as shown in Figure 4 of the drawings. To indicate Sundays and holidays the numerals corresponding to such days may be distinctively colored.

In order to have the rollers 26 work in unison, the outer terminals of the spindles of these rollers are provided with beveled gears 35, which mesh with similar beveled gears 36 keyed or otherwise secured to a longitudinally extending shaft 37. This shaft37 is rotatably mounted in bearings 33 carried by the casing B. If so desired one end of this shaft 37 can be provided with an operating crank 39. Thus if it is desired to operate the rollers 36, the same can be operated from the crank 39 as well from the manipulating handles 27.

This shaft 37 also sup-ports the marker E as will be hereinafter more fully described.

7 The method of finding the length of time in days between any two dates by the calculatingdevice C, will be hereinafter more fully described.

The interest calculating device D comprises an octagonal shaped cylinder 40 and each face of the cylinder 40 has hinged thereto as at 41 a leaf 42. The opposite faces of the leaves 42 and each face of the cylinder is provided with tables for indicating the amount interest at different rates of interest on different amounts for different lengths of time. This cylinder 40 is mounted in any preferred way on an axially disposed shaft or spindle 44 which extends through the side walls 11 of the casing B.

' One end of the shaft spindle 44 is provided with a manipulating handle or wheel 45 and by rotating this wheel 45, the desired interest table can be brought to view inward of the slot 14 and the leaf 42 can be raised on its hinges and swung outwardly of the casing through said slot.

Themarker E includes a hub or sleeve which is slidably and rotatably mounted upon the shaft 37 and this hub or sleeve 50 7 supports an inwardly extending arm 51, the

outer end of which can be enlarged and slotted as at 52 for facilitating the reading of the interest tables on the interest calculating cylinder D.

In operation of the improved interest calculator, suppose a note was made out on November 6th and was presented for payment at the bank on January 15th. The crank 39 or the manipulating handle 27 would be operated so as to move the slide 15 to permit January 15th to be positioned opposite number 1 on scale or section number 17 and by moving the marker up to November 6th, the reading will be found to be days. A glance at the appropriate interest table will give the amount of interest due on a note of a certain amount this length of time and the desired rate of interest. If the note is to be discounted the reading will be found to be 295 days. If the marker is then moved to 295 in right-hand column of section number 17 the interest can be found on another appropriate interestcalculating table.

From the foregoing description, it can be seen that an improved device of simple and compact structure has been provided for giving the correct interest in a mlnimum 7 amount of time on a certain sum of money for a predetermined length of time and at a pre-determined rate of interest. 7

In- Figure 8 I have shown my device modified for use in calculating the cancellation values of insurance policies, calculated from short term cancellation tables.

Herein I have added a fourth column 54.

to the stationary scale 15, this having numerals from zero to a maximum number of months, depending upon the original term of the policy to be cancelled, as for instance, 36 months or three years. Associated with this, and with the movable sections 17, 18 and 19, is a fourth movable ribbon 55, this bearing in rotation the names of the months in the year. Upon the cylinder 40 are placed tables 56 giving the 7 value of the earned and the unearned premium, figured for premiums of various amounts, for instance, from $10.00 up to $90.00.

If it is desired to calculate in March, 1923, the cancellation value of a policy written in June, 1920, for a term of three years, at a premium $20.00, the movable ribbon 55 is set so that the month of March is opposite zero in the stationary ribbon 54. The marker E is then moved up until opposite the thirty-fourth month, or June of departing from the spirit or the scope of this invention.

That I claim as new is 1. In an interest calculating device, a casing, a rotatable cylinder of octagonal shape in cross section mounted in the casing, hinged leaves associated With each face of the cylinder, and interest tables carried by each face of the cylinder and each face of the leaves.

2. In an interest calculating device, a casing having spaced longitudinally extending slots formed in the upper Wall thereof, a cylinder rotatably mounted in the easing adapted to appear through one of the slots having different interest tables associated therewith, a means for determining the length of time and days between any two dates disposed in the casing adapted to appear through the other slot including a longitudinally extending stationary table of numerals divided into threedivisions and consecutively arranged through the three divisions from zero to 365 and a longitudinally movable table including spaced sections each having certain months of the year and the day of each month thereon, the months upon each section being difierent from those upon another section, the months upon the sections comprising the twelve months of the year, a pair of rollers for supporting and actuating the sections, an operating shaft operatively connected with the rollers disposed in front of the casing, means for rotating the shaft, and a marker slidably and rotatably carried by the shaft adapted to extend transversely across the casing and the time calculating device and the interest tables, as and for the purpose specified.

In testimony whereof I affix my signature in presence of two witnesses.

FRANK G. PORTER. lVitnesses C. M. TUCK, H. L. REYNOLDS. 

